1. Field of the Invention
This invention relates to telephone message recording devices, and more particularly to a telephone answering device that provides a number of message areas so that incoming telephone messages can be stored according to the person for whom the message is intended.
2. Description of the Related Art including information disclosed under 37 C.F.R. .sctn..sctn. 1.97-1.99
With the advent of digital electronics, information storage and manipulation has become a more flexibly performed task. With respect to telephone answering devices (TADs), digitization and analog recovery of voice messages allows all the convenience of older, audio tape-based TADs with enhanced message manipulation capabilities derived from the digital storage of the voice message.
The management of memory in digital telephone answering devices is known in the art and has been set forth in detail in U.S. patent application Ser. No. 07/592,673 filed Oct. 4, 1990 and entitled Memory Management Methods for a Digital Telephone Answering Device. This aforementioned patent application is incorporated herein by reference hereto.
It is well-established in the art of telephone answering devices to have a pair of tapes to record and play back voice messages over the telephone. One tape is usually for a single outgoing message ("You have reached my answering machine. Please leave a message after the tone."). The other is for a plurality of incoming messages.
When tapes are used to record messages, the messages are typically fixed relative to each other. Usually, only record, playback, and erase functions can be performed on the messages. No shifting or moving of messages takes place or, if allowed, takes place only under an elaborate and cumbersome circumstances. Such obstacles in manipulating messages are overcome by the use of random access memory (RAM) to store the voice messages.
When tapes are used to record incoming messages for more than one person, messages for one person can easily alternate or otherwise interleave with messages for another person. With tape-based TADs, no means are present by which the messages for just one person can be retrieved while skipping those that have been left for another. A tape-based TAD must retrieve the messages serially and cannot easily skip over messages.
RAM is a very flexible form of digital memory that is increasingly becoming less expensive. With RAM, blocks of memory can be quickly shifted from one location in memory to another and otherwise manipulated. The limitations present in a serial form of data storage are overcome as any particular memory location in RAM is as equally accessible as any other. With tapes or other serial storage media, in order to get to a memory location at the end of the media, all memory locations preceding the end location must be bypassed in order to reach the end memory location.
In order to use RAM to store audio information, especially voice messages, the analog electrical signal representing the audio signal must be converted to a digital form. The voice signal is sampled by a digitizer which generates a number that represents the analog signal at the point it was sampled. By sampling the voice signal at high enough rates, the combined signal levels at each of the sampled points approximates the continuous analog signal originally present. While some of the voice signal is lost by the digitization and re-conversion process, on the whole the process is satisfactory.
Voice digitization and signal recovery are known in the art, as is the manipulation of RAM memory. However, the combination of these known arts have never been embodied in a telephone answering device as set forth herein.
Many systems allow partitioning of messages, but rely on the caller to enter a touch-tone code to access the desired mailbox. However, the caller is the least likely person to know how to direct the message to the appropriate mailbox. This requires the owner to leave lengthy instructions as to how the caller can direct his messages in the system's outgoing message. These instructions not only take time, but if a caller does not follow the instruction, the system breaks down and the call may be misplaced or lost.